Lamp socket adapter



June 11, 1935.

c. L. GOODLIN ET AL LAMP SOCKET ADAPTER Original Filed 001:. 2, 1931 Fly.

mvEgvToRs CarL L. Goodlm and y Thomas J. OMeqm THEIR A TTORNEY Patented June 11, 1935 UNITED Y STATES LAMP SOCKET ADAPTER Carl L. Goodlin, Wilkinsburg, and Thomas J.

OMeara, Pittsburgh, iPa., assignors to The, Union-Switch & Signal Company,.Swi ssva1e, Pa., a corporation of Pennsylvania' Original application October 2, 1931, Serial No.

566,572. Divided and this application August 8, 1934, Serial No..739,000

1 Claim.

Our invention relates to lamp socket adapters, and particularly to adapters for accurately focusing incandescentlamp filaments in precision devices, such as railway signals, although not limited to this field.

The present application is a division of our co-pending application, Serial No. 566,572, filed on October 2, 1931, for lamp socket adapters.

We will describe one form of adapter embodying our invention, and will then point out the novel features thereof in the claim.

In the accompanying drawing, Fig. 1 is a side view, partially in elevation and partially in section, of an adapter embodying our invention, showing a lamp mounted therein and a support on which the adapter is mounted. Fig. 2 is a top plan view of the adapter shown in Fig. 1.

Similar reference characters refer to similar parts in both views.

Referring first to Fig. 1, the device comprises, in general, a support 2, the adapter 3 of our invention and a lamp4.

The support 2 comprises an insulating member of inverted substantially cup shape, and a socket member 6 secured thereto as by rivets 1 extending through laterally projecting portions 9 of the socket member 6 and through the insulating member. A terminal screw or binding post 10 is secured to the insulating member and connected to the socket member 6 as by a conducting strap 12 and the rivet l. A spring connector l4 extends through an aperture l5 in the socket member 2 and is connected to a terminal screw ll. The terminal screws I 0 and I! are provided with heads l9 and nuts 20 at the under and upper sides of the insulating member, respectively. The strap and spring connectors I 2 and l 4, respectively, may be mounted in grooves in the insulating member as shown.

The socket member 6 is of the bayonet type having an accurately machined cylindrical body portion in which slots 22 of the usual substantially J-shape are disposed at the opposite sides thereof.

Referring now also to Fig. 2, the adapter 3 of our invention comprises a cylindrical base member 24 which is adapted to fit into the socket member 6 with a relatively snug sliding fit, and which is provided adjacent its lower end with diametrically opposite bayonet connector pins 25 for cooperation with the slots 22 in the socket member 6. An inwardly extending flange 26. is formed on the upper end of the base member, and this flange engages, with a certain amount of friction, a lamp socket 21 which extends into the basemember 24. By'thismeans; the remainder of the lamp socket being substantially radially spacedfrom the base member 24, the lamp socket "2'! may be moved along andabout the longitudi- 'nalaxis of the base member 24 and still have sufiicient play relative thereto to allow theaxes of the lamp socket member 21 and the base member 24 to be tilted angularly about a pivot in the local zone represented by the inwardly extending annular flange 26. For tilting the socket member 2'! four screws 28 spaced apart are screwed radially through the side wall of the base member and engage at their inner ends the socket member. The screws 28 are all disposed in the same vertical plane and are longitudinally offset from the flange 26.

In assembling the adapter, assuming there are duplicate supports 2, one in service in a railway signaling device and the other at the place of assembly, the adapter 3 is first placed in the support 2 at the place of assembly. Means including a perforated screw and a telescope, not germane to this invention are then employed to determine the position of the lamp filament relative to the socket member 6. By this means, the exact height, angular position, and position of tilt, if any, of the lamp socket axis relative to the axis of the socket member 6 aredetermined.

The angular position of the lamp socket 21 relative to the base member 24 is first adjusted by rotatingthe socket 21 within the flange 26 of the base member to the proper position, after which the height of the lamp socket is adjusted by sliding the lamp socket upwardly or downwardly within the flange 26. The fit between the socket member 21 and the flange 26 of the base member is sufliciently tight so that when the two adjustments just mentioned have been completed, the socket will be temporarily held in its adjusted position by friction. With the height and angular adjustments thus effected, if the filament of the lamp is not at the focal point desired the screws 28 are adjusted until the exact focus is obtained. When the adjustment has been completed, the parts are then fixed in adjusted relation by autogenically joining the same as by spot welding or providing bodies 29 and 30 of solder adjacent to the flange 26 and over the outer ends of the screws 28, respectively, the screws preferably being disposed beneath the surface of the member 24 in the manner shown.

As indicated in Fig. 1, when the lamp is placed in the socket 21 it engages a plunger 3| at the lower end of the socket member. The plunger 3 l, which plunger functions as an electrical connector between the base contact of the lamp 4 and the spring M on the support 2, comprises a shank 32 that slidably extends through an insulating plug 33, a lower end head 34 for engagement with the spring I4, an upper end head 35 for engagement with Lthe center contact element (of the lamp 4, and a *spring 36 for holding the plunger in its upper position until engaged by the lamp. The spring and plunger structure also serves to hold the pins 41 on the lamp 4 :more securely in position in the slots 48 or the "lamp socket 21.

The form of adapter just zdescribed is intended for use with precision type lampsythat is,=with lamps which have their filaments accura'tlypositioned with respect to themase 10f :the lamp. .The adjustments are provided -.toi-.enable ithe =,position of the lamp socket 21 with respect to the base member 24 to be properly located during the process of manufacture without extremely accurate .andshence-costlyimachine work, so thatwwhen the adapter is' placed .-in i the :so'cketmember 6 :shown :in FigrL-anda fprecision .typelampdsmlaced i :the socket r21, ythe .-filament .of the .lamp will :be accurately positioned iwith respect .to.-the sup- Although we have herein shown and described only one form of adapter embodying our invention, it is understood that various changes and modifications may be made therein within the scope of the appended claim without departing fromithe-sp'irit scoperofoourinvention.

Having thus described our invention, what we claim is:

5A lamp socket adapter comprising a cylindrical .basevmember provided at its upper end with an inwardly projecting flange, a lamp socket mem- :'ber extending intossaid base member and having agrelativlyitight fit at the flange and clearance Pblow the 'flange, a plurality of screws screwed through *the-basemcmber in angular spaced relattiona predetermined:distance below said flange and cooperating eat their inner ends with said :socketzmeni'bento provide tilting adjustment of the socket member relative to the axis of the base member, the members being autogenically joined together in their :adjusted :positions;

RCARJL -L. :GQODLIN. THOMAS J. 6).MEARA. 

